Mountain Dew is caffeinated soda. It comes in many different types of flavors other than just the original one such as: Livewire, Code Red, and Voltage, etc. Here is a picture of a can of the original Mountain Dew. *see below* V
Anyway, getting back on the topic of this thread, I personally think that the original MD is the best out of them all.
Wait... there are different kinds of Mountain Dew? I don't think I've ever seen these other kinds. But I guess when you're not looking for them, they're quite easy to miss.